This invention relates generally to the art of heat exchange and more particularly to an apparatus for heating fuel within a fuel tank.
Diesel fuel operated vehicles have proven to be a great boom to transportation because of their ability to operate economically and efficiently; particularly as compared to gasoline operated vehicles. A recurring problem with the operation of diesel fuel powered transportation, however, is the affect of extremely cold temperatures on diesel fuel. In extremes of cold, diesel fuel has a tendency to gel thus making engine operation difficult if not at times impossible. The inventor herein has contributed to devices to alleviate this problem. References are made to U.S. Pat. Nos. 3,929,187 and 4,624,779 and U.S. application Ser. No. 07/309,105 of Feb. 13, 1989.
Several prior art heaters have employed devices which are placed in contact with fuel in the tank for warming the fuel in the tank.
One such device is described in U.S. Pat. No. 4,726,346 to Lucht wherein a heating apparatus is passed into the fuel tank opening and is adapted to fit thereover. An additional apparatus is disclosed in U.S. Pat. No. 4,656,979 to Hoganson wherein an apparatus is placed through an opening in a fuel tank into the fuel and then extends transversely along the bottom of the tank, like a foot, for directly warming the fuel along the bottom of the tank. The above referenced patent to Lucht discloses a similar foot extending transversely within a fuel tank.
U.S. Pat. No. 4,748,960 to Gilbert Wolf discloses an apparatus for intank fuel warming wherein an outlet is partially surrounded by a heating jacket through which a heating fluid is passed. The Wolf patent also discloses a foot type structure.
While these prior art structures have operated somewhat satisfactorily to warm fuel, additional improvements, particularly with regard to intank fuel heaters, are required to render such devices more effective, durable and resistant to vibration and fuel movement.